My suggestion is to stay away from the Red CLovers. According to what I've read (not seen) they are not nearly as palatable as some of the perennial whites. I've seen on this forum where folks like the ladinos and the Imperial CLover. I've had good luch with Imperial's stuff. Mine has lasted 4 years.

As far as weeds go, the amount of competition you have will be up to you. I suggest spraying the plot with Vantage or Poast herbicide as soon as the competing grasses reach 8-10" in the spring. That will eliminate most of the grass and by keeping a eye on the plot thru the summer for late germinating grasses you can expect to get a much longer lifespan out of the field. If you have summer germination from some grass, a second application will be up to you. If they are not too competitive don't worry about them. I kill them to keep them from seeding, consistant mowing will also help with thinner stands of grass. Whatever you decide on, don't let them seed-out.